SPS烧结诱发自蔓延反应制备Ti3SiC2-金刚石复合材料

摘要

采用3Ti/Si/2C单质粉末为结合剂原料,添加适量的金刚石,通过放电等离子烧结诱发自蔓延反应快速制备Ti3SiC2-金刚石复合材料.研究保温时间对复合材料的基体构成和显微形貌的影响.结果表明.3Ti-Si-2C试样经SPS加热,在1170℃左右发生自蔓延反应,形成Ti3SiC2相;产物的主要生成相为Ti3SiC2、Ti5Si3和TiC;在1500℃得到的试样中,Ti3SiC2含量较高,原料反应较充分;在1500℃烧结合金刚石质量分数10％的粉末,得到的试样主相为Ti3SiC2与TiC,同时含有少量的Si、SiC与金刚石;保温1min后得到的试样中Ti3SiC2含量较高,Ti3SiC2相发育成板条状晶粒,与金刚石结合良好;保温5 min后得到的试样中Ti3SiC2含量较低,基体主要由大量的TiC颗粒组成,同时金刚石发生严重石墨化,与基体间形成了较厚的过渡层.%Ti3SiC2-diamond composites were fabricated by spark plasma sintering induced selfpropagation reaction with 3Ti/Si/2C powders as bonder.The effect of holding time on the phase composition and microstructure of composites were studied.The result shows that Ti3 SiC2 phase is formed when heated at 1170 ℃,whose main phases are Ti3SiC2,Ti5Si3 and TiC.It is also found that Ti3SiC2 content in the sample obtained at 1500 ℃ is higher with fully reacted raw materials.The main phase of the sample containing 10wt％0 diamond is TiaSiC2 and TiC.Additionally,small amounts of Si,SiC and diamond are also obtained.Ti3 SiC2 content in the sample with holding time of 1 min is higher,whose grains is lathe-structured and bonds well with diamond.Ti3SiC2 content in the sample with holding time of 5 min is lower,mainly composed of many TiC particles.In addition,the diamond is seriously graphitized,forming thick transition layer.